Bumper jack



June 13, 1939.

BUMPER JACK Original Filgd Sept. 10, 1955 4 -ieamm Z7. $71M Reiuued t... 13, 1939 BUMPER Jack I Leonard n. Nilson, Wayaata, Minm, assignor to Vulcan Manufacturing 00.,

Inc., St. Paul,

Minn., a corporation of Minnesota Original No. 2,064,445, dated December 15, 1936,

Serial No. 39.929, September 10, 1935. Application for reissue 195,568

Ill Claims.

An object of my invention is to provide a bumper jack which is simple, durable and comparatively inexpensive to manufacture.

More particularly it is my object to provide a Jack structure of post-like construction having.

, from a convenient position remote from the jack itself. Present day automobiles are constructed with considerable over-hang of the body relative to the axles and it is therefore quite difficult. especially when balloon tires are used and have been punctured, to get a jack properly positioned under the axle and still .be able to operate the March 12, 1938 Serial No.

Figure l is a side elevation of a bumper jack structure embodying my invention and showing it cooperating with a bumper bar.

Figure 2 is an enlarged sectional view on the line 2-2 of Figure 1 showing the lifting means in lowered position.

Figure 3 is a sectional view similar to the lower end of Figure 2 showing the parts in release or lowered position.

Figure 4 is an enlarged elevation of a portion of Figure 2 as viewed on the line H thereof.

Figure 5 is a sectional view on the line 5-5 of Figure 4; and

Jack from a comfortable position without getting ones clothes dirty and experiencing other difll culties, My present invention accordingly is designed to eliminate the necessity for placing a jack under the axle, the jack being cooperable with the bumper of the automobile which is always located at the extreme end thereof and the jack being sufliciently powerful to lift either one entireend of the carer one ,corner'thereof as desired. I

A further object is to provide operating means for the jack which is in a convenient position for manipulation, specifically, located at the upper end of the post-like jack and vertically reciprocable for the lifting operation without any levers or the like extending laterally from the jack.

A further object is to provide a jack which has a considerable range of movement, one which is readily positioned and only which may be quickly adjusted to the bumper or other projection with which it engages and can thereafter be conveniently operatedin a standing position for lifting the bumper.

Another object is to provide the lifting mechanism of the jack in the form of a lifting piston and a hydraulic pump and to provide readily Figure 6 is an enlarged sectional view on the line Moi-Figure l.

Figure 7 shows a modified form-of load support. 0n the accompanying drawing, I have used the reference numeral III to indicate a base or foot for my jack structure. It is provided with up struck perforated ears I! through which a pivot pin H extends. The pin also extends through a lower cylinderlhead ll of a lifting cylinder IS. The lifting cylinder I8 is enlarged at its upper end to forms reservoir 20 and the upper end is provided with ahead 22 and a packing nut 24.

Within the liftingcylinder I8 I provide a cup leather lifting piston 28 connected with a tubular lifting piston rod 28. The upper end of the rod 28 extends through the packing nut 24 and is connected by lock nuts 20 to ayoke 32. The arms of the yoke indicated at 12c extenddownwardly outside the reservoir 20 and are hooked at their lower ends as indicated at 34. The hooks enter slots 36 of a tubular lifting member 38 The internal diameter of the member 38 is provided with a plurality of guide strips 4|! which operable release means permitting lowering of the jack without any manipulation thereof, other than opening a release valve.

With these and other-objects in 'view, my invention consists in the construction, arrangement. and combination of the various parts of my device, whereby the objects contemplated are attained as hereinafter'more fully set forth, pointed out in my claims and illustrateddn the accompanying drawing, in which:

provide a four point guide as shown in Figure 6 for the entire tubular lifting member or for the portion thereof extending below the reservoir.

The lifting member 38 is provided with a pair.

of hook-like projections 42 and 44. One of these is adapted to engage a bumper bar 46 of an auto mobile or any other device to be raised by the lack structure.

, From the foregoing description, it will be obvious that the lifting member 3| can be raised by operating the lifting piston 20 and this is accomplished by .pumping oil from the reservoir 20 and to the space in the cylinder below the piston. For this purpose, I provide a pump comprising a pump cylinder ll, a plunger rod 50, intake valves 52 and an outlet valve 54. The intake valves are 55 the space in the cylinder l8 above the piston 26 s gravity seated while the outlet valve is seated by a spring ,56. The plunger 50 has an enlarged rod-like extension or operating rod SI to provide sufficient strength to prevent bending, the plunger 5 itself being quite small to secure the required differential of diameter between the pump plunger II and the lifting piston 26.

The upper end of the operating rod extends from the upper end of the tubular lifting piston 24 through a packing nut Gil and terminates in an operating knob 62. Upon reciprocation of the knob 62 upwardly, oil will be drawn from the reservoir Ill, through the check valves 52 into the pump cylinder 4!. On the down stroke, this oil will be forced through the outlet check valve 54 and raise the lifting piston a distance corresponding to the volume of oil pumped through the valve. Thus by a. number of reciprocations the bumper 46 will be raised step by step. With the jack. structure in the lowered; posi-,-

tion, it is first placed adjacent the bumper and the yoke 32 then grasped and pulled upwardly which causes flow of oil through the check valves 52 and 54 so that the jack may be quickly raised by hand to contact with the bumper. Thereafter the jack may be pumped up for the lifting operation. This eliminates the tedious operation of v pumping to bring the jack up from its lowered position to bumper contacting position and enables the operator to raise it to this position in a minimum of time.

After the jack is raised, it will'stay in raised position, the valves check 52 and 64 holding the toil against return movement. Such return move- I ment is required for lowering the jack and may be accomplished by releasing means which I'will now describe:

. Means is provided for by-passing the return oil past the valves 52 instead of unseating them be noted, is threaded in a fitting 68 which connects the lower end of the tubular piston rod 2| with the lifting piston 26.

The upper end of the pump cylinder 48 is prov vided with a head ll having a plurality of notches 12. The operating rod 50 is provided with a head 14 having a plurality .of lugs 16 4 adapted to enter the notches 12 when the rod .58 is adjacent its innermost position as shown in Figure 2. I

Thereupon the knob 02 can be rotated for rotating the cylinder 48 and causing it to move longitudinally downward as in Figure 3 to open the valve plug. and to engage and opcn the valve 54. The oil may thereupon flow past the valve 54' and enter the bore of the cylinder 48 through" notches in the lower end thereof, and

then through passages 18 (see'Figure 3), and past notches 12' causing a pin-like extension 64 on 7 the lower end of the piston rod II to moire the cylinder ll above the piston .28 and to the reservalve I4 further from its seat. This cannot be done while the valve 54 is on its seat due to the pressure of oil holding the valve, against its seat, but. after the valve is unseated the pressure is equalized, thereby permitting a downward movement of the knob 82 to open the valve further for quick lowering without exerting undue effort to push the valve further open.

In Figure 7 I showa modified construction in which a sleeve 34a. is substituted for the sleeve 38 and has a movable ring 42a provided with a lug 44a, thus providing. an adjustable hook on the lifting sleeve "a. The surface of the sleeve 38a is preferably slightly corrugated so as to aid in the binding action of the ring 42a on the sleeve after the ring is adjusted tothe desired height thereon. 1

It will be noted that all operating parts of the jack are in a straight line. This produces compactness without any projecting operating parts to be interfered with by parts of the automobile,

inasmuch as parts above the bumpers of automobiles are always clear. Likewise, the absence of particularly an operating handle projecting laterally from the postlike jack makes the jack less bulky to place in a tool-box after use.

The elongated arrangement of the jack persui'ilcient capacityin the reservoir for. displacement caused by the tubular piston rod 28. The guide strips 4| effectively guide the tubular lifting member 38. in its lower positions, the upper end thereof being finally guided by the reservoir 20 and capable of extending to a position partially thereabove ,when the jack is in its extreme raised position}. The foot, being pivoted, can be swung to the dotted position of Figure 1 when storing the jack in the tool box so as to thus iurther reduce the room required for storing thejack to a minimum.

Some changes may be made in the construction and arrangement of the parts of my device without departing from the real; spirit and purpose of my invention and it is my intention to cover. by my claims any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

h ml myi ven m, 1. In" a" bumper jack, a vertical cylinder, bumper engaging means slidable thereon and having means for supporting a bumper, lifting means within said cylinder and having a por-- tion projecting above the upper end thereof, an

operative connection between said portionand said bumper engaging means to raise the bumper engaging means when the lifting means is operated, operating means for said lifting means having .a vertically reciprocable stem extending out 'of the upper end of said portion, a handle vthereom'sc'rew threaded. means to release said lifting means to permit lowering thereof, said handle. and stem, in their lowermost position,

being .manipulatable to rotate said screw thread ed meansand thereby operate said release means.

- 2. vIn a bumper jack, a vertical cylinder, bumper engaging means slidable thereon and having means for supporting a bumper, a lifting piston within said cylinder and having a piston rod projecting above the upper end thereof, an op- 1 erative connection between said portion and said bumper engaging means to raise the means when oil is pumped to the lifting piston and a pump within said piston rod for so pumping oil, said pump having an operating rod extending from the upper end of said piston rod, release means for said lifting piston, said operating rod .being connectible therewith when the rod is in its lowermost position to operate the release means when it isv desired to permit the jack to lower.

3.1-In a jack of the character described, a verably thereby, said operating member being substantially within the extended outline of said lifting member.

4. In a jack of the character described, a vertical cylinder a lifting member slidable longitudinally relative thereto, lifting means within said cylinder, fsaid lifting means comprising a lifting piston, a tubular piston rod extending upwardly therefrom and from the upper end of said cylinder. the lower end of said tubular piston rod and the space in said cylinder above said piston constituting a reservoir, an operative connection between the upper end of said tubular piston rod and said lifting member, a pump within said tubular piston rodfor pumping oil from said reservoir above the lifting piston to the cylinder below the lifting piston and an operating member for said pump extending from the upper end of said tubular piston rod, comprising a pump piston rod and a knob on the upper \end thereof and packing between said piston rods to seal one relative to the other.

5. In a Jack of the character described, a vertical cylinder, a lifting member slidable longitudinally relative thereto, lifting means within said cylinder, said lifting means comprising a lifting piston, a tubular piston rod extending upwardly therefrom and out of the upper end of said cylinder, an operative connection between the upper end of said tubular piston rod and said lifting member, a pump within said tubular piston rod for pumping oil from the cylinder above the lifting piston to-the cylinder below the lifting piston, an operating member for said pump extending from the upper end of said tubular piston rod, said pump including release means to permit oil to flow from below the lifting piston to thereabove and means to render said release means operative by coactlon of said qoperating fiiember therewith in the lowermost position of the operating member.

8. m a device of the class described, a vertical cylinder having an enlarged reservoir portion at its upper end. guide means below said reservoir portion of substantially the same diameter as the outside diameter of said .reservoir portion, a tubular lifting member vertically slidable on said guide means and reservoir portion, lifting means within said cylinder comprising a lifting piston, a tubular-piston rod extending upwardly at one end from the upper end of said ai,1 1a

of its movement the first way.

cylinder, an operative connection between the upper end of said tubular piston rod and said lifting member, a pump within said tubular piston rod for pumping oil from the reservoir cylinder above the lifting piston to the cylinder 5 below the lifting piston and an operating member for said pump extending from the upper end of said tubular piston rod.

7. In a jack of the character described, a vertical cylinder, a lifting member slidable longitudinally relative thereto, lifting means within said cylinder, said liftingmeans comprising a lifting piston, a tubular piston rod extending upwardly therefrom and from the upper end of said cylinder, an operative connection between the upper end of said cylinder, an operative connection between the upper end of said tubular piston rod. and said lifting member, a pump within said tubular piston rod for pumping oil from the cylinder above the lifting piston to the cylinder below the lifting piston, an operating member and release means for said pump extending from the upper end of said tubular piston rod, and a coupling connection between said pump piston rod and said release means, therelease means being operated upon rotation, said coupling connection being operative by said pump piston rod only at one limit of its reciprocatorym'ovement.

8. In a jack of the characterdescribed, a vertical cylinder, a lifting member slidable longitudi- 31y nally relative thereto, lifting means within said cylinder, said lifting means comprising a lifting piston, a tubular piston rod extending upwardly therefrom and from the upper end of said cylinder, an operative connection between the upper J5 an operating member? for said pump extending from the upper end of said tubular piston rod and comprising a pump piston rod and knob on the upper end thereof, said pump including valve means to permit, when open, oil to flow from below the lifting piston to thereabove, screw threaded means to open said valve means and means operable from said operating member to operate said screw threaded means. 7

9. In a jack of the character described, a ver-- tical cylinder, a lifting member slidable longitudinally relative thereto, hydraulic lifting means a within said cylinder and projecting thereabove, an operative connection between the projecting part thereof and said lifting member and pump means for lifting and lowering said lifting means and 5' having apiston rod projecting from said projecting part, said piston rod being movable one way for lifting operations and movable a different way for lowering operations at one limit only 10. In a jack structure of the character described, a-vertical support, a lifting sleeve slidable longitudinally relative thereto. hydraulic lifting means for said lifting sleeve, lowering means for said liftingmeans, an operative conm nection between said lifting means and said lifting sleeve, means for operating said lifting means and having a handle projecting above said lifting sleeve and means exterior of said jack structure for. operating said lowering means, said han- 7 die being operable by reciprocation along the vertical axis of said Jack structure and being substantially within the extended outline thereof.

LEONARD D. NILSON. 

